Half Log or Full Log - Seems to be a question of religion

[Longbow]

I am preparing to build a home in NW Wisconsin (Read COLD winters) well not this year.. :D . But anyway, as I interview builders one of the basics seems to be the uncompromising position on either side of the half vs full log question.

We are concerned about energy efficiency being 30 miles from Lake Superior. I understand it is hard to compare R values as Full logs don't really have one per se. but still an opinion without a hard philosophical position would be nice. The fact that there are strong positions each way makes me skeptical of both sides. I have also heard each side claim less air leakage.

For example: The full log properly sealed vs Tyvek with nail holes OR Settling and uneven log shrinkage vs sealed and insulated between wall setup.

There are plenty of good local builders representing a number of nationally marketed Log Home manufacturers. I have toured a couple of brands manufacturing plants and have read enough log home magazines that I am starting to consider insulating with the back issues. :shock:

Any perspectives would be welcome!

[DYork]

I didn't keep it's url, but I read a study just the other day by Texas A&M Univ's Forestry Lab giving a R rating for solid wood logs/inch. Unfortunately, I don't remember exactly what it stated and don't want to go posting any bum scoop.

I'll see if I can find it again.

Couldn't find it. Here's one from another forum citing a study by 'The Gubment'. Take from it what you can, cause It's over my head.

http://www.handhewnloghomes.com/EnergyEfficiency/energy_effieciency_of_log_homes.htm

[Longbow]

Thanks for the link....I always appreciate results from my tax dollars!

[H2OFowlerandWife]

Hi Eric,

My husband and I live down by Eau Claire, if you know where that is. We also own land in Barnes. My husband also has a friend that's a carpenter, and I'm pretty sure his outfit built a log home last fall for someone if you would like to possibly use him as a resource.

Good Luck!

[RockEngineer]

The Bonneville Power Authority (BPA) did a study of the energy efficiency of a bunch of log homes in Northern Idaho years ago. "The Thermal Performance and Air Leakage Characteristics of Six Log Homes in Idaho" from BPA's RCDP Cycle 3. They had cold winters and hot summers. Their main finding was that if you seal the air leaks, log homes are very energy efficient and qualify as "Super Good Sense" energy efficient homes. Their study was mostly with full round chinked log homes with average 12" diameter logs if I remember correctly.

The main thing with any type of log home is to be sure to seal the air leaks if you want energy efficiency. Each method of log home building has its own techniques for doing this. Some work well, some don't. Depending on what style of log home you will need to do your research. The LHBA method with rebar and chinking if followed can be good at stopping air leaks and be energy efficient. If someone doesn't follow the methods and is not careful about sealing air leaks they can have problems.

The coped chinkless styles can also be efficient if you make sure all the gaps are filled. You have to account for the settling in most of these and all things don't settle evenly. Sometimes they have to be helped along (rods & springs) or your have to go back later and make adjustment in your trim and look for gaps and leaks. There are about as many techniques as there are log home builders.

I personally don't like building a log home on the outside and then building a framed house inside of it which many of your insulated log homes tend to be. That is my personal preference.

Real log homes can be efficient if you make sure they are built right. There are lots of people out there for the quick buck who don't put the time and care into making sure the house is efficient over the long run. There are also some very concientious builders. You have to do your research.

Good Luck. :lol: :lol:

[Longbow]

Hi Eric,

My husband and I live down by Eau Claire, if you know where that is. We also own land in Barnes. My husband also has a friend that's a carpenter, and I'm pretty sure his outfit built a log home last fall for someone if you would like to possibly use him as a resource.

Good Luck!
That's funny, we are building in Barnes! We're on Upper Eau Claire. I was also IN Eau Claire last week as well. Small world. Who is your husbands friend?

[Longbow]

Real log homes can be efficient if you make sure they are built right. There are lots of people out there for the quick buck who don't put the time and care into making sure the house is efficient over the long run. There are also some very concientious builders. You have to do your research.

Good Luck. :lol: :lol:

Research is the word. We are torn at this point. I have talked to a fair number of home owners of both persuasions and so far the good news is that they are all happy, half and full. We have been looking at Confederation log homes (Full log) and Wilderness Log homes (Can do either, but recommend half with their Insullog system.) Both have local dealers/GC's.

[RockEngineer]

Since my main involvement is making sure all the beams, joists and connections are properly sized and showing that the log home will stand up during wind and seismic loading, I don't hear much back from clients when things go well and everyone is happy. I hear back when they have problems with a contractor or what they got was not what they expected and want to know if there is some way I can help them. They always express that they are happy with the work I did for them and how friendly and helpful I was but want advice on how to deal with "that other guy".

I haven't dealt with either of the companies you are dealing with. I mostly deal with hand crafters, people doing their own log homes from raw logs through LHBA or modified log homes like Sing Square Logs.

Good Luck. :lol: :lol:

[Longbow]

I haven't dealt with either of the companies you are dealing with. I mostly deal with hand crafters, people doing their own log homes from raw logs through LHBA or modified log homes like Sing Square Logs.

Good Luck. :lol: :lol:Thanks Richard,

Doesn't really matter what type of home you are building. It seems it is always exciting and nerve wracking at the same time..:D

[BCarrierJones]

Eric,
If you are serious about researching all of your options, my advice (and that of The Association's, I believe), is to come to a class. You will learn more here than you will from any 'interested' party who would also like to sell you their home kit. I was very wary of making this kind of an investment and, actually, had to save for quite a while to make it happen. But I want to tell you that it was worth it to someone else who is also in the researching phase.
B

[kahle]

When you look at the insulating qualities of logs you have to take into account two factors. R-value (The resistance to the movement of heat) and Heat Capacity (sometimes called dyanamic R value or thermal mass) or the ability to store heat. Most cured wood has an R value of about 3 per inch. A log house with 12" logs is only R-36 at the thickest part of the logs. The average is usually around R-20 which is about the same as a 2x6 framed wall with fiberglass insulation.

However, the heat capacity logs is far graeter than that of a frame insuated wall. This capacity works best when the climate displays large swings in temperture. For example -20 at night and 30 during the day. The heat capacity has the ability to delay your wall's response to these extremes so that the interior temperature stays very close to the mean.

One of the most interesting properties of heat capacity is that it is radiate heat and is not diminished even if there is air infiltration through the walls.

If you add in the effect of sunlight through south facing glass and against the exterior walls and you will find that even without an additional heat source the interior temperature will be more moderate (neither too hot or too cold) than in most other types of constuction.

The definitive test was conducted in 1977 by order of Congress. HUD was ordered to test the effect of wall mass on space heating and cooling loads. They built 6 test houses at Gaithersburg, MD, frame, frame insulated, brick, brick w interior insulation, brick w exterior insulation and log. They put a heat pump inside each house and set it at a constant temp and left them for a year measuring the energy draw for the pump. The log house beat them all even with a big crack in one wall (probably a kit cabin)

[DYork]

Thanks for that info kahle!! That govt entity has changed it's name in recent years I believe, but they are still the primary source for most accepted standards. * As I understand it, the full NIST report is available for the asking, tho I'm not sure just how to go about getting one, and I suspect it is a lengthy read. Just the 3rd party summary found here (http://www.loghomes.org/uploads/The%20Energy%20Performance%20of%20Log%20Homes1.PDF ) is nearly 30 pages. (PDF format-Acrobat Reader required)

A shorter version is here (http://www.timmerhem.se/site/Test.htm). HTML

* NIST=National Institute of Standards and Technology.